Dissertation

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PiDVS: User experience research for an embedded digital vinyl system

Sam Spreadborough 11019351

Sam Spreadborough

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Abstract This dissertation project looks examine what Human Computer Interaction (HCI) methodologies are available for evaluating the efficacy of an embedded Digital Vinyl System for DJs, and then use these methodologies to design and implement a complete user experience. The project will look to produce a finished product at the end built around the Raspberry Pi maker board.

Using a User Centred Design (UCD) process, the design requirements were identified using a mixture of group studies, self-reporting questionnaire, and review of existing products. The design requirements were that the product must have a visual audio waveform, a file table, BPM display, time display and hot-cues. A prototype was developed and improved through iteration based upon user testing research.

The final UX design and product fulfilled the essential design requirements and selfreporting questionnaire scores reported either positive or neither positive or negative response for all the usability metrics, and users reported improved satisfaction when comparing the first iteration to the last.

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Acknowledgments I would like to acknowledge my dissertation supervisor Dr Chris Nash for his help and support with this project. He has helped realise an idea that I have had since I started DJing.

I would also like to thank Richard Perry for supporting me through my various career path changes and for (mostly) being the voice of reason.

Lastly, I would like to acknowledge Lindsey Wiltshire, because he said if I did he’d acknowledge me back. Here you go, then lad!

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Table of Contents Abstract................................................................................... 2 Acknowledgments.....................................................................3 1

Introduction........................................................................8

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Literature Review................................................................9

2.1 Understanding the user............................................................................................................9 2.1.1 Definition of DJ and Turntablism..........................................................................................9 2.1.2 Appropriation of new digital technologies.........................................................................10 2.1.3 Resurgence in Vinyl............................................................................................................11 2.1.4 Modern day Turntablism....................................................................................................12 2.2 Understanding the methods...................................................................................................14 2.2.1 Human Computer Interaction development.......................................................................14 2.2.2 The human computer.........................................................................................................15 2.2.3 Interaction Design models..................................................................................................17

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Project Design...................................................................18

3.1 Design introduction................................................................................................................18 3.1.1 Outline/aims of the project................................................................................................18 3.1.2 Personal background in the culture....................................................................................18 3.2 User centred design approach................................................................................................18 3.2.1 DJing use case....................................................................................................................19 3.2.2 Usability Goals...................................................................................................................20 3.3 Identifying the user base........................................................................................................20 3.3.1 Defining the user types......................................................................................................20

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Technical design considerations..........................................24

4.1 Outline of hardware used.......................................................................................................24 4.2 Rejected Hardware.................................................................................................................25 4.3 Rejected Form-Factors............................................................................................................25 4.4 Code design............................................................................................................................30 4.4.1 Toolkits...............................................................................................................................30

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Requirements Capture.......................................................31

5.1 Research Overview.................................................................................................................31 5.2 Participants.............................................................................................................................31 5.3 Research of similar products and projects..............................................................................32 5.3.1 Methodology......................................................................................................................32 5.4 Mini group study....................................................................................................................33 5.4.1 Methodology......................................................................................................................33 5.5 Active participation in the culture..........................................................................................34 5.6 Usability Testing – “Think Aloud” testing................................................................................34 5.6.1 Methodology......................................................................................................................34 5.7 Self-reporting questionnaire...................................................................................................36 5.7.1 Methodology......................................................................................................................36

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Testing and Evaluation.......................................................37

6.1 Existing products....................................................................................................................37 6.1.1 Introduction.......................................................................................................................37 6.2 Mini group study....................................................................................................................38

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5 6.2.1 Requirements capture........................................................................................................38 6.2.2 Group product design task.................................................................................................39 6.3 User test 1 – Initial single page UI design...............................................................................40 6.3.1 Overview of design.............................................................................................................40 6.3.2 Talk Aloud Test Analysis......................................................................................................41 6.3.3 Self-Reporting Questionnaire Analysis...............................................................................42 6.4 User Test 2 – Modal tile design...............................................................................................44 6.4.1 Overview of Design changes..............................................................................................44 6.4.2 Talk Aloud Test Analysis......................................................................................................49 6.4.3 Self-Reporting Questionnaire Analysis...............................................................................49 6.5 User Test 3 – Improved modal tile design with greater affordance.........................................52 6.5.1 Overview of Design changes..............................................................................................52 6.5.2 Talk Aloud Test Analysis......................................................................................................57 6.5.3 Self-Reporting Questionnaire Analysis...............................................................................57

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Conclusion......................................................................... 59

7.1 Summary................................................................................................................................59 7.2 Evaluation of finished product................................................................................................59 7.3 Future work............................................................................................................................60 7.3.1 Changes to hardware.........................................................................................................60

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References........................................................................62

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Appendix........................................................................... 69

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“If there is any instrument that has achieved both the musical and the iconic status of the guitar in dance music, it is the turntable�

(Montano, E. 2008).

Figure 1 - DJ Jazzy Jeff at the Red Bull Thre3Style Showcase 2012

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1 Introduction The DJ; once a term used to describe a person who simply played vinyl records on the radio has now transcended it’s broadcasting beginnings and is now a multi-billion-dollar industry as stated in the 2015 IMS Business Report (a financial report of the electronic dance music industry in North America). The same report details how the DJ technology industry was worth 0.75 billion dollars, and that 1.6 billion dollars was spent at festivals and clubs, cementing the DJ as the new “rock star” (Watson, 2015).

DJ practitioners now have a wider range of equipment from which to apply their craft than ever before. Gone are the days of two turntables and a mixer; DJs can now use equipment such as USB MIDI controllers, CD players, Multimedia players and touch screen tablets which bring with it new and interesting play styles. New DJs beginning out have a plethora of functionality to choose from and it has never been easy to be a DJ. This dissertation will examine the User Experience (UX) of these different DJing product categories and look to draw some conclusions that will inform the design and implementation of a product that will enable vinyl DJs the ability to play digital music files from an external USB source and allow them to manipulate the playback using an analogue vinyl turntable.

The research question will be split into two parts; design and implementation. To design the product, it is essential to know what it is that the user will want to and expect to do with it.

So, it is essential to conduct some requirements capture research. The research question is: “What design requirements do DJs have for an embedded Digital Vinyl System turntable?”

Once the design has been concluded, it is useful to know whether the product has been successful in addressing and implementing these requirements. So, the final research question is: “What Human Computing Interaction (HCI) methodologies are there for evaluating the efficacy of an embedded Digital Vinyl System user experience?”

This dissertation will give an overview of the history of DJing looking at the early pioneers of turntable mixing, and its development alongside the music industry. It will cover how the DJ industry has changed with the changing of music formats and increases in computing power.

There will be a discussion around the changing views of vinyl DJing with regards to changes in technology. Many DJs feel that vinyl DJing is the most authentic form of DJing and can become very defensive when trying to protect that status. Advances in technology have caused some vinyl DJs to be very protective of their craft.

Later it will highlight some key Human-Computer Interaction (HCI) areas of research, and outline some methodologies that will be useful for completing this project. A key Sam Spreadborough

8 methodology covered is the User Centred Design (UCD) from which much of the design of this project was based.

Beginning the research, it will outline the research methods used in the requirements capture, later going on to give comparisons of existing commercial and non-commercial products and projects related to this project. As well as existing product research, a group study was conducted with participants from the UWE DJ Society and the methods will be detailed.

In the design stage, this dissertation will list the iterative process results showing the changing User Interface (UI) as well as UX considerations that were found from the user testing research that was conducted. Each iteration will detail the UI and user testing results, concluding with the problems raised and solutions offered.

To conclude, a summary of the results will be stated. The project will be evaluated on the success of the implemented requirements and will offer some avenues for further research and project development.

2 Literature Review 2.1 Understanding the user 2.1.1 Definition of DJ and Turntablism The DJ has been around as long as there has been recorded music, however it wasn’t until 1935 when the term “DJ” was coined combining the words “disc”, referring to the records, and “jockey” a machine operator (Fisher, 2007, p11).

Ahmed, A.Y et al (2012) gives the following description of a DJ:

“The traditional craft of the DJ lies in the skilful manipulation of vinyl records on turntable platters and especially in ‘beat matching’ – i.e., the smooth mixing of one track into the next.”

This description gives the view of the DJ as a jukebox, however this view is not shared by Bakker and Bakker (2006) who state: “Club DJs do not refer to their practices as ‘playing records’. Instead they engage in ’turntablism’” alluding to a description of DJing “evolving into an artistry in its own right”.

A turntablist is a DJ whose musicianship derives from the skilful use of advanced scratch and cut techniques and is different from a DJ who just “plays” records. Turntablists view the turntable as an instrument that can be “played” (Sanden, 2013). If DJing is described as the “skilful manipulation of vinyl records” then turntablism can be described as the art of that skill.

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9 Newman, M (2003) cites an interview by Alex Ogg and David Upshal where DJ Kool Herc explains the beginnings of turntablism: “I was using some of the breakdown parts. Every Jamaican record has a dub side to it. So, I just tried to apply that. As the years went along I’m watching people, waiting for this particular break in it, the rhythm section. One night, I was waiting for the record to play out. Maybe there are dancers waiting for this particular break. I could have a couple more records for the same break in it – I won’t, how it be if I put them all together and I told them ‘I’m going to try something new tonight. I’m going to call it a merry-go-round’. The B-Boys, as I call it, the energetic person, they’re waiting just to release this energy when this break comes in”.

By mixing this new “break-beat” style of DJing with the MC, Kool Herc lay the foundations of what would later become Hip-Hop. Grandmaster Flash developed this style further and using his electronics skills, developed the first mixer with cueing functionality (being able to audition a deck’s audio inside of headphones before being played aloud). He worked out a system whereby the break of a record could be looped indefinitely using two identical records; cueing one track whilst the other is playing and alternating (Newman, M. 2003).

2.1.2 Appropriation of new digital technologies DJ’s have always been generally accepting of appropriating new technology into their craft.

Turntablism pioneer Grandmaster Flash during his performances would use a VOX Percussion King to complement his turntablist technique (Hot97, 2016) pioneering beatboxing (which would later become ‘Beatboxing’ or ‘Human Beatboxing’; the simulation of the beatbox sound using the human voice).

In the early 90s, as the analogue vinyl format was becoming replaced in favour of the new digital compact disc (CD), DJ’s were quick to see the benefit of using it. The CD allowed the DJ the ability to reduce the weight of their ‘crate’ (a milk crate that was traditionally used to carry vinyl records to their gigs), and along with the release of home CD burners, allowed DJ’s to bring their own remixes and productions.

To complement the new digital revolution, a new CD turntable was needed; the Pioneer CDJ. The CDJ allowed DJs the ability to manually manipulate the sounds on their CDs using the conventional turntable techniques that they had learned from turntables. The CDJ had a pitch fader, the same as the Technics 1210, and had a static platter that allowed the DJ to ‘pitch-bend’ their tracks. Although not the first company to release a CD turntable, Pioneer because the most popular. Technics had failed to recapture the new digital crowd with their SL-DZ1200, a CD turntable with a rotating platter resembling the platter on a Technics 1210.

Levitt says of the DJs she interviewed “nearly half” cited the Pioneer CDJ1000 as “the product that convinced them it would be possible to shift away from vinyl” (Levitt, 2015).

This shift to digital would later be cemented with the introduction of vinyl emulation software known as the Digital Vinyl System (DVS). DVS allowed DJs the ability to manually Sam Spreadborough

10 manipulate a piece of control vinyl to control the playback of a digital music file using a control tone. The control tone, once decoded, gives software speed, direction and position of the vinyl which can be mapped to a digital music file such that it gives the impression that the digital music file is pressed directly on to the vinyl itself. DVS became widely accepted by many DJs as it enabled them to play long sets without the backbreaking labour of carrying a long set’s worth of vinyl, whilst simultaneously utilising their hard-earned turntablism skills.

With the rise of digital DJing and software there was inevitably going to be a backlash regarding what “proper” DJing was.

“The club and underground club DJs are very judgmental, almost to the point of discriminating against other DJs who might not have the same level of skill they have.

Ability to manipulate vinyl is a technical skill that is highly respected and that differentiates DJs among themselves.” (Bakker and Bakker, 2006) Nothing divided opinion amongst DJs quite like the Sync function. Sync is a function that allows DJs to beat match records automatically using beat grids and visual displays. DJWORX covered the subject in an article titled “Sync – The Big Red Button” (Settle, 2012). Although the article was largely pragmatic and un-damning of the sync functionality, it had a heated debated in the comments section. What is the art of DJing if it’s not “the skilful manipulation of vinyl records”? Is it still an art if the skill can be achieved with a single push of a button?

When making comparisons between vinyl and computer DJing, many DJs criticise computer DJs for their apparent lack of skill thus being inauthentic (Montano, 2010). In Serato DJ version 1.5.0 they included the sync feature to their software, but felt they had to include the following in the blog post: “Simple Sync is here for DJs that want to use it with Control Vinyl/CDs. If it’s not your thing just disable it and never see it again :)” (Serato, 2013) However, Levitt (2015) explains that the posturing of DJs about this subject may be a moot point; the audience’s experience isn’t necessarily affected by the DJ’s choice of equipment.

Levitt explains how one dancer said: “As long as I like the music, as long as they’re playing with some skill and originality, I don’t care what they use.”

2.1.3 Resurgence in Vinyl Although DJs are now predominately using digital formats and computer based DJing methods, vinyl has not been relegated to a legacy format just yet. Vinyl sales hit their highest peak since 1997 in 2011, and when Daft Punk’s Random Access Memories sold over 19,000 copies on vinyl in 2013 the press really hailed vinyl’s resurgence. Vinyl sales had continued to increase 2011-2013 in part due to Record Store Day (an idea conceived by independent music stored to raise media attention in the failing record store industry) (Levitt, 2015, p123). Vinyl records are now the fasted growing area of the music sales market (Bartmanski and Woodward, 2013).

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The vinyl manages to persist in its cultural appeal due to a mixture of nostalgia and the desire for music to be tangible. The iconicity of vinyl refers to Pop and Rock music’s heritage, and vinyl is seen to be more authentic. A musical heritage of classic albums is important to many people wishing to enjoy the album as it was originally released, and to some, is seen to be the pinnacle musical experience. Bartmanski and Woodward (2013) discuss the “ritualistic engagements” that vinyl brings; the music becomes an active experience rather than a passive one due to the listener not be able to take the music elsewhere.

Time magazine offers another explanation in their article titled “Here's Why Music Lovers Are Turning to Vinyl and Dropping Digital” where they cite John Lloyd (a music genre specialist from Juno Records) describing “throwaway culture of music” with regards to the increasingly low quality of digital music. The increased manufacturing costs and sale price of vinyl means that for the purveyor of new vinyl records must undergo extensive quality control, and for the purchaser the increased cost gives an assurance of quality and the sense of an investment (Gibson, 2015).

DJs now have a lot more options of how they wish to use vinyl, either in the sense of playing records directly, or through the manipulation of digital records with vinyl through DVS. The UK based internet vinyl music subscription service Wax and Stamp have built a business model like the early DJ pools. For a monthly fee, they will deliver a curated selection of vinyl records to a DJ’s door (Wax and Stamp, 2017).

2.1.4 Modern day Turntablism The vinyl format may not have changed much, but the way that DJs perform with it has.

2.1.4.1Hybrid turntablism Many DJs are now including turntablist routines in to their electronic music sets. Artists such as DJ Shiftee use a Traktor Kontrol S8 and turntables to create unique hybrid sets consisting of classic Turntablist cuts and scratches, and Controllerist cue juggling and effects (Native Instruments, 2015).

2.1.4.2Portabalism A new and exciting area for DJing technology is around the area Portablism. DJ Tech Tools give this description: “Portablism is the practice of DJing (most commonly in a turntablism-style fashion) with easily transportable gear.” (White, 2016) Products like the now discontinued Vestax QFO (championed by DMC World Champion DJ Qbert (DJ Qbert, 2017) are used by DJs wishing to perform cuts and scratches in less formal situations (including busking), and generally consist of minimal controls and external audio inputs for beats and music. Like other instruments, Portablism looks to make turntablism a more sociable experience by bringing the decks out of the booth.

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Figure 2 - Technics SL1210 mk2: The staple DJ turntable

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2.2 Understanding the methods 2.2.1 Human Computer Interaction development Human-Computer Interaction (HCI) is an interdisciplinary design science that applies experimental psychology methodologies to computer science, and looks to remove the negative aspects of the user experience, whilst improving the positive ones. It is the design, implementation, and evaluation of these interactions and looks to provide a framework to produce products that are easy, efficient and a pleasure to use (Shneiderman et al, 2013, p 4).

Jaimesa, A. and Sebe, N. (2007) describe the three main actors in HCI: User System Interaction

The person who interacts with a system.

Computer technology.

The way the user interacts with the system.

It is clear to see that from a developer’s point of view it is important to not only understand technology engineering, but also a wider range of aspects not limited to psychology and cognitive science, sociology and ergonomics. HCI is a multifaceted subject and you need to take a holistic approach when designing systems.

The field of HCI first became recognised as an essential field when large room sized mainframe computers moved from being operated by trained professionals and morphed into minicomputers for home/office computing (models such as the Apple Model II and the commodore) (Lazar et al, 2010, p 2). For computer manufacturers to be profitable, there was a commercial need to make them as accessible as possible.

Research in the late 80’s was more focussed around interactions that people made to complete tasks such as word processing and databases, which led to the creation of UI elements such as windows, error messages and dialog boxes (Lazar et al, 2010, p3).

However, one of the first examples of HCI was the idea of hypertext; the idea that a document can contain links to other documents so that a user can follow a trail to find other documents. The concept was first proposed in now famous Memex desk, where Vannevar Bush considered the idea: “A memex is a device in which an individual stores all his books, records, and communications, and which is mechanized so that it may be consulted with exceeding speed and flexibility. “ Hypertext is the modern-day evolution of the “building a trail of many items” concept proposed, and is central to how the World Wide Web operates (Bush, 1945).

GUI’s offer a visual contextual representation of data available on the computer, and it became necessary for the nature in which the user interacts with this data to change. A direct manipulation device was needed.

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14 Based on the Xerox PARC input device, the mouse proved to be just the device which was made popular with the Apple Lisa in 1982 and with the Apple Macintosh in 1984 (Myers, 1998, p 4). However, in more modern times, there has been a shift of focus on the human finger being the manipulation device through touch screen interfaces, allowing the user to touch the data they’re interested in. Albinsson and Zhai (2003) identify the unique design considerations needed with touchscreen UI. Firstly, the finger obscures the information that the user is pointing on and secondly the fidelity of the finger as a “low-resolution” pointing device.

Research conducted by Shneiderman and Andrews (1991) concluded that a “Take Off” method of pressing the screen and moving the finger to an area and then releasing the finger proved to the most effective for high precision tasks; a technique that is used in Apple iOS for moving a cursor in text.

2.2.2 The human computer When considering HCI it is clear how analogous the way human and computer are in terms of information processing.

Model Human Processor Card, Moran and Newell (1983) proposed their model of how human’s process information using three systems of processing; the perceptual, motor and cognitive systems. The perceptual system is the memory store for visual and auditory cues from the external environment through the human sense. The cognitive system uses information symbolically encoded in the working and long-term memory stores to plan and execute behaviour, and the motor system is the actions that the cognitive system executes. Card, Moran and Newell explain how the interconnection and parallel processing of these systems establishes the performance that a human processes information.

The computer works in a similar fashion, with the perceptual model being an interface device transmitting electrical signals indicating input to the CPU (cognitive system) which in turn executes a procedure based on internal coded instructions. The computer then provides a feedback that could be by displaying information on a screen or by interacting with hardware (motor system).

Using this procedural and compartmentalised model, you can begin to design systems that work for both the human and the computer.

GOMS (Goals, Operations, Methods, Selection rules) model The GOMS model of design looks to break down the system design process four parts. The top level is the Goal; what is the user trying to achieve. This is often written using simple abstracted statements (e.g browse the web). Second are the operations; the actions/steps that the user must take to accomplish the goal (e.g double-click, drag mouse). Thirdly are the methods which is a procedure of linked operations that a user must complete, and lastly if there is more than a single way to achieve the same goal (e.g use shortcut; browse Start menu) then the selection is the user’s choice of method.

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15 This GOMS model is useful in that it breaks down a user’s behaviour in to simple steps that can be used for providing an engineering framework, or for evaluating the effectiveness of a system (the time spent on each operation can be calculated and compared) (Lorin, 2002).

The task-artefact cycle GOMS is a linear model of working and doesn’t take in to consideration the evolving nature of the user and how they use a system. The task-artefact cycle explains how a feedback loop between the task and artefact (end goal) can create new possibilities for ways of working and artefacts that can be created. Task-Artefact cycle gives a model for how systems can adapt with changing environments and can never reach an optimal state (Soegaard and Friss Dam, 2016).

Inviting exploration Norman explains that the easiest way for a user to learn a computer system is to invite exploration and experimentation and outline three requirements for this. Firstly, a system’s allowable actions should be visible to the user inviting and reminding them of what is possible to achieve. Secondly, the outcome of these actions should be easily interpretable to the user to give a good understanding of cause and effect. Lastly, he explains a user should be able to reverse any action if the action is undesirable, give clear explanation to the user of what the action will do is irreversible, or make irreversible actions hard to execute (Norman, 2002, pp183-184).

Norman’s affordances Affordance is about utilising conceptual models of what an action is. A specific hardware push button doesn’t need explain to someone who has never seen it, as they will have a conceptual model what it is and thus how it should operate. Norman offers two principles for designing using this principle: 1. Provide a good conceptual model.

An action should provide a conceptual model that can allow a user to predict the outcome of the action. A bad conceptual model will provide no reasoning behind why an action provides that effect, and will give no clues as to what to do to remedy if something goes wrong.

2. Make things visible.

The actions should be obvious, with clear relationships between the controls and what’s being controlled. Single functions should have single controls.

(Norman, 2002, pp 21-22).

The Gestalt Principles The Gestalt principles explain how people perceive the relationship between objects in a space. The six laws show how people group seemingly unrelated items together based on their relationship to each, for example the law of proximity shows how objects close together are perceived as belonging together (Chang et al, 2001). Hogue (2012) gives an example of this in web design; grouped tabs on a webpage are seen as belonging together,

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16 and when a drop-down box appears items inside that box are perceived as belonging together because they are all moving in the same direction.

Understanding these principles is critical when building UI as it plays it helps you to build a user centred design by exploiting user’s internalised understanding of how objects relate to each other, and ascribes some meaning to a UI object’s effects. Chang et al (2001) note that few of the Gestalt principles are used in interface designs they investigated in 2001, and concluded that from their user evaluations that all the Gestalt principles are beneficial to learning effectiveness.

Fitts’ Law Fitts’ Law is a mathematical equation for predicting the speed-accuracy characteristics of human movement. The importance of this law in touch screen UI design is that it gives direction for the placement and size of UI elements to enable the highest level of accuracy.

When designing touch screen UI for musical devices, it is even more important as many interactions are time critical.

(Soegaard et al, 2016).

2.2.3 Interaction Design models Goal orientated design is key to the way we should design products. If we design in a way that allows users to achieve goals, they will be happy, fulfilled and eager to recommend them to other people.

User centred design Extending the “inviting exploration” model, User Centred Design (UCD) is about understanding human behaviour and should utilise natural relationships between things.

Norman explains that a user should ideally instinctively understand how to use a system, however if instruction needs to be given it should not have to be repeated.

Norman offers seven tenets to good UCD: 1. A system should look to exploit a user’s internalised understanding of how something should work (mental model theory).

2. The number of operations to completing a task should be kept to a minimum to avoid over complexity.

3. Users should understand the action and its effect before they execute it.

4. The mode of interactions (e.g buttons) should reflect the action and its effect, and should be ergonomically displayed.

5. Constrain what a user can do, so they can only do the right thing.

6. Think about what errors could occur and design support for the user.

7. If something can’t be uniquely designed, use standardisation.

(Norman, 2002, p 9-22) Staggers and Norcio (1993) expand on the mental model theory by explaining that users will think in terms of “metaphors and analogies” when forming mental models. User’s will use an internal mental model when faced with a new experience, and will use this to test hypotheses of what the new experience represents.

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3 Project Design 3.1 Design introduction 3.1.1 Outline/aims of the project In this section, the outlines and aims for the project will be discussed.

For a practicing DVS DJ, the current use case it that you bring with you to a performance a laptop computer with DVS software and an external 2 in / 2 out soundcard (Serato DVS, 2017). During changeovers, you would disconnect the previous DJs DVS audio card and connect your own, then connect all the audio cables together. This can be time consuming and, if not executed in the correct sequence of actions, can result in a disruption to the audio output to the audience.

For a practicing CDJ user, the use case is much simpler. The DJ simply brings a single USB with their music properly formatted using the Pioneer Rekordbox software and plug in directly to the player in an available slot.

For a DVS user to have the same functionality, a new product must be produced that will enable the DJ to plug a single USB in and select and perform songs without the need for a separate laptop and soundcard setup.

3.1.2 Personal background in the culture The researcher is a DJ with 5 years’ experience playing in multiple venues around Bristol. The researcher has played on a variety of different DJ equipment types, including controllers, CD players, multimedia players and DVS. As part of university, the researcher founded the UWE DJ Society and taught its members for two years in technique (using multiple equipment types), troubleshooting, etiquette and performance styles.

The researcher is, as of the time of writing, the resident DJ for the Students’ Union at UWE.

3.2 User centred design approach This project will be following a user centred design approach, as such will consist of the following key design stages: User needs will be established using experimental research methods.

A user model will be created by analysing use cases from ethnographical studies and from experimental research.

The tasks will be analysed to engineer the operations and methods that the user will take, taking in to consider design heuristics.

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18 Usability testing will be conducted to ensure that users can complete their goal and that they derive enjoyment from the process. This will be completed using prototyping and an iterative design process.

(Nissen et al, 2007, pp 214-215) 3.2.1 DJing use case To build a successful DJ product, it is important to understand what the typical digital DJing use case is: “What is it that a DJ does? What is the process that a DJ goes through when planning and playing a DJ gig?”

A DJ’s most important asset is their music collection which is always being updated with new releases. Ahmed et al (2012) describes the importance that DJs give to relevant metadata in digital files, such as the tempo and musical key. Many digital DJs will use bespoke specialist music library managers such as Rekordbox (Pioneer, 2016) or Beatport Pro (Beatport, 2017) which contain functionality to extract or process files to attain this metadata. Companies such as Mixed In Key (2017) have made a business model out of offering software that performs this functionality.

Ahmed et al (2012, p 1812) makes a mention of “alternative recommender systems”; a system that provides song suggestions based on existing metadata and a DJ’s music collection. Kado is one such system that analyses music played from over 500,000 DJ sets and provides song suggestions to a DJ based on their music collection (Kado, 2016). The Discover feature in Spotify also serves a similar purpose (Spotify, 2017).

The DJ Blond:ish explains in an overview video for Beatport Pro how she categorises new music with custom metadata values based on the “mood” tag and explains how she adds tags based on “nostalgic moments” such as Burning Man festival. When it comes to deciding on what music to perform at a performance, she uses the wealth of tags she has developed to narrow down music selection choices (Beatport, 2015). This process is analogous to vinyl DJing and “crate digging” (Serato use the term “crates” when referring to digital playlists (Serato, 2016, p28)). Ahmed et al (2012) explains that this is an exploratory process where DJs will seek to find some cohesive element to a selection of tracks, either in a vocal hook, melody, drum beat or overall sound.

When performing, the order in which the DJ chooses to play their records is more fluid than may be suggested by process of song playlist preparation; DJs are looking for indirect communication from the crowd to direct the flow and choice of records. Also, the slot in which the DJ has been booked to play will influence the choice and pace of the performance, with warm up slots being slower songs and peak time being faster ones (Ahmed et al, 2012, p 1810).

Secrecy is also important to DJs when playing as they may have a rare or unknown record that they would wish to be “theirs” and not have other DJs copy their collection. The Sam Spreadborough

19 uniqueness of a DJs set and music collection can be their unique selling point. Vinyl DJs would put white stickers over the centre of the records to hide the title (Ahmed et al, 2012, p 1811), and digital software such as Serato now have an “AM Mode” (Serato, 2016, p 68).

The final aspect to the gig is ending it. Depending on the time of the evening and slot being played, it involves either handing over to a new DJ or stopping the music.

3.2.2 Usability Goals After an understanding of the needs of the DJ, it is important to decide how these needs will be tested to ensure that they have been met. Rogers et al (2011) set out the following usability goals for effective interaction design which serves as a useful structure for usability testing questions: 1. Effectiveness describes how good the product is in general at doing what it’s supposed to do.  This project should be intuitive and keep to current DJing conventions for interface design, and the project must load and being playing music files quickly.

2. Efficiency is the support the product offers to the user to carry out their tasks.  This project should facilitate fast searching and playing of audio files, and require as minimum as possible steps to complete this and should playback digital audio files with no audible latency.

3. Safety – Trying to eliminate undesirable situations a user experiences.  This software should be bug free and should protect the user against undesirable situations such as loading a track on to a playing deck.

4. Utility is the functionality that the product provides, and should include everything that user expects and wants.  This software should provide the essential functionality requirements and in a way that is easily accessible to the user.

5. Learnability describes how easy a system is to learn.  This system should allow the DJ to perform with virtuosity.

6. Memorability is how well a user can recall the steps needed to complete certain tasks.  This system should be simple and require no relearning.

3.3 Identifying the user base 3.3.1 Defining the user types

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20 DJs have various performance styles, and with these different styles comes different ways of working. Whereas before a DJ’s only method of playing music would be from Vinyl records and a turntable, there are increasingly becoming a range of equipment to perform.

For the purposes of this project a scale has been devised: Traditi Augm onal ented Turnt Turnt ablist Scale ablist

Contro Hy llerist bri Orient d Equipment exampleated

Traditional Turntablist

Contro llerist Special ist

Description

Full analogue turntables

Figure 3 - Technics SL1210

Augmented Turntablist

A turntable that has been digitally augmented to allow connection to digital devices, but operate as turntables.

Figure 4 - Reloop RP 8000

Figure 5 - Gemini CDT-05

Hybrid

MIDI controllers that require external computers to operate. Their music manipulation interaction device derives from the turntable and have rotating platters.

Figure 6 - Numark NS7

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21

Figure 7 - Numark V7

Controllerist Orientated

Digital media player that can operate independently of an external computer that include jog wheels or similar interaction devices

Figure 8 - Pioneer CDJ 1000

Figure 9 - Pioneer CDJ 2000

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22 Figure 10 - Denon MCX8000

Controllerist Specialist

Controllers that are operated by an external computer but the interaction device is not derived from a platter or jog wheel.

Figure 11 - Traktor Kontrol S8

Figure 12 - Akai APC 40 mk2

This project will have a target audience of those who fit between scale reference 1 and 4 as its primarily an augmented turntable with multimedia playback capabilities.

Equipment such as the CDJ share much of the functionality and aesthetic of the Turntablist type (platter, pitch adjustment). This was designed such that DJs moving from vinyl to CD would have a smaller learning curve.

The scale draws a parallel to Montano (2008, p 412); the Controllerist end of the scale afford greater visible manipulation of music than the turntablist end where Controllerists rely heavier on their laptop screen to get feedback.

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4 Technical design considerations 4.1 Outline of hardware used Many combinations of hardware were tried for this project; however, the final hardware set is the following: Raspberry Pi 3 Model B This hobbyist maker board was chosen because it is a cheap component, and has a wide range of compatible hardware that work with the GPIO (General Purpose In/Out) header pins.

Audio Injector sound card At the time of writing, this is the only soundcard that fits directly on the Raspberry Pi GPIO header pins that has stereo phono inputs and outputs. The benefit to using a soundcard that can utilise the GPIO is that it reduces latency over using USB, and that it can attached directly to the Raspberry Pi. Official Raspberry Pi Touch Screen Similarly, to the Audio Injector sound card, this is compatible with the Raspberry Pi’s mounting screws, so the Raspberry Pi and Audio Injector sound card can be directly mounted to the screen.

The screen itself is a multitouch device, and using JUCE’s multitouch API it will be possible to implement some interesting multitouch gestures.

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Figure 13 - Assembled hardware (Back view)

Figure 14 - Assembled hardware (side view)

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4.2 Rejected Hardware Behringer U-Phono UFO202 Originally selected for its built-in phono preamp, the USB audio device was rejected in favour of the Audio Injector as the Audio Injector interfaces directly through the GPIO header pins offering two advantages; lower latency and required no trailing cables.

(Behringer, 2016) Makibes Raspberry Pi 7 Inch Capacitive Touch Screen LCD An excellent 1024x600 7-inch display that was rejected due to requiring a trailing HDMI cable to connect video output and USB to provide power and touch functionality. It was originally selected as the original form factor was going to be much larger. The Raspberry Pi Official touch screen offers multi-touch capability and it connected via a display ribbon cable creating a much neater project. Also, the official touch screen has mounting points to connect the Raspberry Pi to (Waveshare, 2016).

4.3 Rejected Form-Factors Figure 15 – 20 show rejected form-factors for the PiDVS project. Design 1 – 4 were all designed to house the rejected hardware, and were ultimately too large to be a suitable laptop replacement (design 4 is almost the size of a laptop).

Originally, the project was going to use a custom turntable head shell to deliver audio to and from the PiDVS based upon the ICE head shell (DJs Dream Customs, 2015). A custom head shell was built and it is shown in Figure 15. It was rejected due to low quality build materials, however it was tested and functioned as expected (see figure 13).

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Figure 15 - Rejected design 1.

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Figure 16 - Rejected design 2 – Designed By Mike Soper

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Figure 17 - Rejected design 3 - Side view

Figure 18 - Rejected design - Top view

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Figure 19 - Rejected design 4 - Front view – Designed By Mike Soper

Figure 20 - Rejected design - Back view – Designed By Mike Soper

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4.4 Code design 4.4.1 Toolkits JUCE The JUCE framework was chosen for it specialisation with audio applications (JUCE, 2017).

The framework includes all necessary classes to get the application running on the Raspberry Pi running Raspbian Jessie (a Raspberry Pi based custom build of Debian Linux.

Raspbian 2017).

The Projucer (a JUCE project creator and IDE) was used to design the user interface using its GUI for UI design.

Following instructions from the JUCE community (Web, D. 2011), it was possible to set up a JUCE project to produce a Linux makefile that can compile the application on the Raspberry Pi. XWAX XWAX is an open-source DVS application written in C for Linux. The software is used in many other open source DJ applications, such as MIXXX, to decode a variety of Timecode vinyl brands (Hills, M, 2016). The decoding functions were incorporated into a C++ wrapper class and used in the project.

One of the great features of using the XWAX timecoder functions is that it includes a software preamp function.

TagLib TagLib is an open source library used for extracting metadata from digital audio files. This library was used to extract track information such as, track/artist name, BPM and artwork (LalinskĂ˝ and Wheeler, 2016).

SoundTouch The SoundTouch library is another open source library used to time stretching and pitch shifting audio. Although originally the intention to use this produce pitch lock functionality to the project, this library also includes a BPM detection algorithm, so this was integrated to analyse BPM if the metadata doesn’t already contain it (Parviainen, 2015).

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5 Requirements Capture 5.1 Research Overview Multiple research methods were used in this project which were chosen to answer two questions: “What are my design requirements?”

For the requirements capture stage of the research, the following methods were used:  



Research of similar products and projects Mini group study o Self-reporting questionnaire. o Group discussion o Ideal product design activity Active participation in the culture “Were the design requirements successfully implemented?”

For the requirements implementation evaluation, the following methods were used:  

Think-aloud user testing Self-reporting questionnaire

5.2 Participants The participants for this research were collected using opportunity sampling from the UWE DJ Society. Participants were students of varying DJing abilities and experience, all attending a timetabled DJ lesson.

The participants had used a small variety of DJing systems but, due to the available equipment at the lessons, all participants had used the Pioneer Rekordbox system of multimedia players.

Consent Informed consent was gained from all participants for all aspects of the research. They were given information on the project prior to completing a consent form. Participants were informed they leave the experiment at any time and that they informed how their information would be used.

Opportunity Sampling Participants were students attending lessons on how to learn how to DJ. The feedback gathered will be from the point of view of somehow who is still acquiring the necessary

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32 skills, and may not have used other equipment types to give a thorough critique of the project The numbers of students attending the lessons was low, possibly due to the time of the lessons (late evening) and during a heavy coursework period.

Equipment Use Cases Very few participants had used vinyl before so many of the feature requests made were to include existing CDJ and software functionality rather than Vinyl specific features.

User Testing All students were male, so not representative of an overall DJing population.

Age The age of the participants was between 19-25, and not representative of an overall DJing population.

Occupations None of the participants were professional working DJs.

5.3 Research of similar products and projects 5.3.1 Methodology By analysing existing products is possible to extract trends and themes that can inform an initial knowledge base and a starting set of design requirements.

For this project, multiple DJ technologies were analysed to find similarities in interaction design and functionality. Manufacturer’s websites and user manuals were analysed from the following technology groups:      

Conventional turntables and conventional vinyl Compact Disc players Multimedia players MIDI Controllers with DJing software Digital Vinyl Systems with DJing software Tablet computer touch software

Manufacturers will conduct their own research and development when designing products and their products will reflect the researched use cases. Whilst a useful exercise for finding trends, it does not highlight new ideas, only existing ones.

Examined products can be found in Appendix 3.1.

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5.4 Mini group study 5.4.1 Methodology Purpose The purpose of using study groups is to gain direct feedback from individuals with an interest in the subject. Group studies are a great way to begin research and gather some initial direction for further research (Lazar et al, 2010, pp 178).

Outline of plan The participants were asked to participate in 3 activities: Self-reporting questionnaire – A questionnaire was issued to all willing participants to gain an overview of participants DJing experience and preferred equipment types.

This questionnaire was brief and was used to guide the whole group discussion giving discussion points.

Whole group discussion – Participants were asked as part of a larger group conversation to expand further on their preferred DJing equipment setup with the hope that it would spark a discussion about the positive and negative aspects to these setups. The participants were then guided to provide a list of design requirements including functionality.

The group discussion questions were broadly: 1. “What do people currently use?”

2. “Why is that?”

3. “What is your preferred setup for DJing?”  If the group have experience using DVS systems or conventional vinyl, discuss what systems they use.  If not “What aspects of vinyl DJing put you off using vinyl?”.

4. “What features make DJing easier for you?” - Group may require prompting to make sure they cover all feature types, e.g user interface controls, file management, usability, learnability etc.

5. “What aspects of different setups do you dislike?” - Group may need prompting to cover all aspects Group task – The group was split in to smaller self-selecting groups and asked to design the user interface for their ideal DJing product, and asked to list functions and features that this product should have.

The group study was video recorded for later analysis.

Strengths Focus groups offer a way to explore a subject by giving members an opportunity to provide detailed responses. Using open ended questions and secondary follow up questions, it is possible to extract a lot of information.

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34 Weaknesses It is possible that the conversation could be dominated by a few participants meaning the views and opinions of other members are not heard. Analysing answers can time consuming through viewing recorded footage and making notes.

Analysis The group task was used to compare design choices between participant groups, and the list of functions and features was collated with the group discussion design requirements to produce a working list of requirements.

5.5 Active participation in the culture Being involved in many DJing activities with other DJs affords a deeper understanding of the needs of the DJ for this project. While it does introduce researcher bias, the benefits of that deeper understanding coupled with knowledge of UX design provides a great platform to design intuitive products.

5.6 Usability Testing – “Think Aloud” testing 5.6.1 Methodology Purpose Usability Testing means giving a representative group of users’ representative tasks to complete in a representative environment using prototypes (Lewis, 2006). The prototype in this research was a high-fidelity working proof of concept prototype, and the purpose of this research was to test the design choices were efficient (Lazar et at, 2010, p 260). A “Think Aloud” testing method was chosen as it allows the researcher to be able to understand the thought process a user by asking them to verbalise it.

Outline of plan Users were asked to use the PiDVS device for 10 minutes to perform some DJ mixing with no instruction to how it works. The users were asked to verbalise what they were doing and offer any criticisms of the system (including UI, UX, form factor etc.). The 10-minute testing session was recorded from above so that the hand movements of the user could be analysed later.

Users were encouraged to verbalise their actions and thought process, and if required, the research would intervene if they forgot to verbalise or if they were struggling to use the PiDVS. Where possible conversation between the user and the research was avoided, however occasionally this was not possible.

Immediately following the think aloud test, a self-reporting questionnaire was given to the participant to complete. The participants were asked to give a Likert score based upon statements relating to the usability goals as stated previously (see “Self-Reporting Questionniare”) Analysis Sam Spreadborough

35 Tullis, T. and Albert, B. (2010) give a framework for measuring metrics which was adapted for this project. Task success, errors and issues, and behavioural based metrics approach was devised, and the criteria are as follows: Task Success Metric: The task metric was simple; could the participant use the project to complete a basic mix?

Although DJing mixing can be subjective in what could be considered a basic mix, the criteria used for this are (ibid., p 64): 1. The DJ could match the BPM of two songs.

2. They could blend two songs together with little/no beat phase problems.

Issues-based Metrics: The issues-based metric was used to identify technical issues that prevent/hinder a user’s experience with the product.

Tullis and Albert offer a 3-rating severity system for categorising issues:  Low – “Any issue that annoys or frustrates participants but does not play a role in task failure".  Medium - "Any issue that contributes to but does not directly prevent task failure"  High – “Any issue that directly leads to task failure” (ibid., p 104).

Errors-Based Metrics An errors-based metric was chosen to identify any flaws with the design choices. The errors were categorised using the following terms: A. Slip – “Unintended action a user makes while trying to do something on an interface even though the goal is correct”.

B. Mistake – “Unintended action a user makes while trying to do something on an interface if the goal is incorrect”.

C. User Interface Problem – “Error in understanding or performing an action due to the user interface” D. Equipment (other than project) failure - If the turntable or mixer has an error. (ibid., p 106).

Behavioural The comments from users were codified based on a positive-negative scale: A. B. C. D. E. F. G. H.

Strongly positive comments.

Other positive comments.

Strongly negative comments.

Other negative comments.

Suggestions for improvements.

Questions.

Variation from expectation.

Stated confusion or lack of understanding.

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36 I. Stated frustration.

All metrics were logged with a timestamp for future debugging and design review. The metrics were not used to compare scores between users due to individual differences found between each user, however they were used as reference to guide design changes.

5.7 Self-reporting questionnaire 5.7.1 Methodology A self-reporting questionnaire was used in the requirement capture stage for all participants of the group study, and then again after every user testing session.

At the requirements capture stage, participants were asked about their experience with DJ equipment, what they enjoyed and didn’t enjoy about that hardware and what design aspects they would like to see for an embedded DVS product.

For the requirement evaluation stage, a questionnaire was given to each participant once their product testing had finished. The purpose was to gain a quantitative satisfaction score based on the user’s experience with using the device. The statements are based on the usability goals detailed previously, and the scores are then collected and compared to show if any changes to the user experience have been successful.

Outline of plan After the speak aloud test, users are asked to complete a questionnaire whereby they are asked to rate their opinion to a statement made using a Likert scale. There is a section at the end that asks directly if they’d like to leave any comments or suggestions for improvements.

The questions were designed to directly address whether the usability goals had been achieved. A -2 – 2 scale was chosen such that in the analysis a negative score would indicate that the usability goal had not been achieved, and a positive score would indicate it had.

The statements were: Effectiveness

“The playback of the music file was fluid with no discernible audio errors” “The file was quick to load” “I was able to carry out the tasks in a way I’d want to do them” “I would feel confident using this as my primary DJing setup”

Efficiency

“The application was fast to navigate” “I was able to find the music file I wanted to play quickly”

Utility

“I was able to find all the functions and features that I wanted to use easily” “All the information I wanted was easily accessible” “The application gave me enough visual feedback”

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37 “The application had all of the functionality that I need”

Learnability

“The application was easy to learn” “I feel confident that I could use the product quickly and without errors”

Memorability

“I feel confident I could remember how to use this again”

There was a section for written feedback asking for improvements and overall thoughts.

Analysis The same questionnaire was given to every user immediately after the think aloud test to gauge their opinion on how well the usability goals were achieved. Using a Likert scale, it was possible to compare test results and gain ongoing feedback on areas that could be achieved. In the final test, it was also used to compare the first design to the final design to clarify whether the changes were positive improvements and that the finished product was better.

Users were also given an opportunity to prove qualitative feedback such as what they felt needed to be changed and what they thought worked well. These comments, along with the think aloud testing provided a work goals to be completed before the next user test.

6 Testing and Evaluation 6.1 Existing products 6.1.1 Introduction After examining many DJ products in various product categories, the following UX requirements were identified: Waveform All software products featured a visual waveform of the DJ track that is used as a visual aid.

BPM All software products featured a BPM readout display of the BPM of a track, and when a DJ manipulates the speed of the track, the resulting BPM is adjusted to reflect this new speed.

Track Library All software products had a method for displaying playlists and music tracks within those playlists for a DJ to browse. The library displays file metadata such as Track Title, Artist Name and BPM. The library should also have a method for searching and sorting music.

Hot Cues and Loops Sam Spreadborough

38 All software products had a facility to enable the DJ to store and execute multiple cue points and loops. Almost all hardware products had dedicated hardware buttons to facilitate this functionality.

Time elapsed/remaining display All software products featured a visual feedback element to indicate the amount of time that has been played of a song.

There has become a blurred line between product groups with many modern commercial products will include elements from other product group.

1. Compact Disc players can use DVS software using timecode CDs. 2. Serato DJ includes a companion tablet computer app for use as a MIDI controller.

3. The Pioneer DDJ-SP1 can be used as a complimentary MIDI controller for Serato, or plugged directly in to their multimedia players.

4. Tablet computer software now has support for a selection of MIDI controllers.

5. Tonetable is a tablet computer app that emulates the output of a time coded DVS vinyl.

6.2 Mini group study 6.2.1 Requirements capture Participant experience questionnaire Most of the participants had used a Pioneer CDJ and only one had used a Digital Vinyl System. One participants reported having used conventional vinyl.

Based on the group discussion, and the feature list group activity, the following requirements were identified: 1. BPM readout The participants stated that they found it difficult to perform effectively without this information.

2. Key information Many participants identified this. Although some participants did not find this information useful, for those that did stated that they heavily relied upon it. Referencing the range of Pioneer Rekordbox compatible multimedia player range, one participant mentioned how they relied on the compatible key function; where songs with compatible musical keys are highlighted in the library.

3. Beat Counter For those who used the Pioneer Rekordbox players, mentioned that this was essential to them for being able to visually line up musical phrases.

4. Waveform Unanimously this was stated as their must have feature.

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39 5. Hot Cues 6. Rekordbox compatible With Pioneer equipment being so widely used, many participants have music playlists that reside only in the Rekordbox software, so many expressed a wish to retain their playlists formatted to work with this software. Rekordbox software is proprietary, so this functionality would not be possible to incorporate.

These requirements also qualify the requirement results obtained from researching existing products.

When asked about form factors, some participants in the group stated they’d like to see this project as a stand along product and not built in to a turntable.

6.2.2 Group product design task There was a range of different design styles including one depicting an existing product and one showing multiple screens of information and functionality.

All preferred a minimalistic interface design was preferred, showing fewer functionality options and showing essential information such as the waveform and BPM. A dark colour scheme was most useful due to the dark environments where the DJs worked.

One notable design was from Group 2 who depicted a modal user interface that abstracts lower level functionality in favour of a more minimalistic design with the option to get at higher level information.

Group 4 described a multimodal interaction design that utilised physical buttons as well as a touch screen interface. They described how they were opposed to a touch screen interface as they felt it didn’t give the kind of tactile feedback they needed to perform.

Group 1’s design was derivative of a Pioneer CDJ 2000. Group 3’s contained many requirements discussed, however the group didn’t engage well with the task. 1

1 Group 1 discussed not liking touch screen interfaces and desired physical buttons. A MIDI scroll wheel was developed using an Arduino Teensy and a hardware digital encoder knob.

The scroll wheel functioned as expected, allowing the user to scroll the file table and load tracks, however the form factor was not fully explored due to time constraints.

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6.3 User test 1 – Initial single page UI design 6.3.1 Overview of design Once the design requirements had been established, a lengthy process of designing and implementing the functionality, form, and interface of the project began.

The following is a screenshot of the first prototype software. It is a single screen application, apart from when the user touches the “Settings” button which brings up a pop up window with various application settings.

1. The “Load” button – Once the user has selected a song from the file table by tapping it, this button begins the playback of the selected track.

2. Waveform – This is a scrolling waveform of the audio being played. The user can zoom in and out of this waveform to their own preference.

3. Cue points – A user first taps on a blank cue point to set it, and then once set, taps it to return to that cue point.

4. File table – Displays the available playlists and tracks within that playlist for selection.

5. Search – Tapping on the search text box brings up an onscreen keyboard that allows the user to input a search term.

1 2 5

3 4

Figure 21 - Shows the main window of the first prototype of the PiDVS user interface

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Figure 22 - Shows the pop out window for the audio settings.

6.3.2 Talk Aloud Test Analysis From the user testing, the following points were raised: 

Of the 5 participants who took part, hardware issues raised by the participants.



The users reported that they felt the files loaded quickly and they could find the file they wanted to play fast.



Despite some users having never used vinyl turntables before, all participants reported that they thought positively of the project.



Most common feedback was a lack of functionality that they were used to: BPM display Key display Track overview waveform



Most reported wanting to be able to scroll using their finger on the main file table list, rather than relying on the scrollbar.



All but one participant failed to notice that the project had cue points.



All participants showed that they’d like to be able to go back to the beginning of the track. The participants either manipulated the vinyl until they were at the beginning or pressed the “Load” button to get back to the beginning.

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42 

There were some issues with the turntables due to the need for maintenance. The grounding of them wasn’t correct, and this influenced the performance of the project.

6.3.3 Self-Reporting Questionnaire Analysis

User Test 1 - Self-reflective questionnaire mean average score 2

1.5

1

0.5

0 Q1

Q2

Q3

Q4

Q5

Q6

Q7

Q8

Q9

Q10

Q11

Q12

Q13

-0.5

-1 Figure 23 - Shows the self-reflective questionnaire scores for test 1. Participants reported positive scores in all areas except for functionality, confidence in using as primary DJ setup and being able to carry out tasks in the way they would like.

“The playback of the music file was fluid with no discernible audio errors” “The file was quick to load” “The application was fast to navigate” “I was able to find the music file I wanted to play quickly” “I was able to find all the functions and features that I wanted to use easily” “All the information I wanted was easily accessible” “The application gave me enough visual feedback” “The application had all of the functionality that I need” “I would feel confident using this as my primary DJing setup” “I was able to carry out the tasks in a way I’d want to do them” “The application was easy to learn” “I feel confident that I could use the product quickly and without errors” “I feel confident I could remember how to use this again”

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Mean Average

Standard Deviation

0.80 1.80 1.20 1.40

1.10 0.45 0.84 0.90

0.40 0.20 0.80 0.00 -0.20 -0.40 1.20

0.89 1.30 0.45 0.71 1.10 0.55 0.45

0.20 1.60

0.84 0.55

43 The participants responded positively that they thought the project was quick to operate and that they felt confident they would be able to remember how to use it again, however they stated that it didn’t have all the functionality that they wanted, and they weren’t confident that they want to use it as their main DJ setup.

Errors that prevent task completion

1. Audible squeal from audio glitch. The software outputs glitch when the play head is pulled back behind the beginning of the audio track.

2. Software detecting grounding issues as timecode pitch, and an audible glitch is heard.

3. User not able to find out how to load track.

4. Left deck screen went to standby mode.

5. Software crash.

6. When app settings are launched, the sound stops.

Based on the user test and the questionnaire, the following changes were highlighted: Suggestions for Improvements

1. Add cue point label.

2. Scrolling touching the main screen rather than scroll bar.

3. BPM information in library and main playback screen.

4. Wow and flutter correction.

5. Colour coded musical key information.

6. Bigger scrolling waveform.

7. Static waveform overview.

8. Loops.

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6.4 User Test 2 – Modal tile design 6.4.1 Overview of Design changes A new design was in development before the beginning of the group study. It was later adapted to work with a UI developed based on feedback and group study activities.

Figure 24 - Shows the “Play” section of the second UI design.

Figure 25 - Shows the “Browse” section of the second UI design.

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Figure 26 - Shows the “Settings” section of the second UI design.

New design style Based on the ideal product design task from the group study, a new design style was coded.

It is based on group 2’s “tiles” based system. The different “tiles” represent abstracted information e.g. the Settings tile shows an overview of the information contained within the screen it opens; the play screen shows a waveform. This follows the Gestalt law of Proximity.

This style represents an abstract concept as a visual language; an icon represents what the “Tile” is about. This UI was designed to use as little written language as possible, and that each “Tile” should show an overview of what the underlying screen is about e.g the Library “Tile” shows a library symbol and shows the currently playing track and artist name.

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Figure 27 - Shows the “Overview” section of the third UI design. Each “Tile” is a button with an icon that represents what screen the button accesses.

Cue points Users reported not realising that there were cue points, and were unaware that the buttons on screen performed that function.

The cue points have now been added to the play screen inside a tabbed component. The tab has been labelled “Cues” to give better clarity to what the buttons represent.

Waveform Users reported that the size of the waveform was too small, and wished for a much larger one.

A secondary static audio overview waveform has been added in response to a request. The overview waveform is visible no matter what screen the user is on. Dragging on the static waveform performs a scrubbing function.

Master Tempo Pitch Lock was made possible by using the SoundTouch library and the pitch shifting algorithm.

Loops In response to a request for the feature, a Loop function was implemented and included in the Cue tabbed component.

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Figure 28 - Shows the “Play” section of the third UI design. Cues and loops are better presented inside a secondary tabbed component.

File table From testing, it became evident that the users expected to be able scroll the file table by dragging the table list using their finger rather than using the scrollbar.

The scroll bar for the file table and the playlist table has been removed, and the underlying code was altered to accepted a draggable table.

BPM Users reported that they wished to be able to see the BPM of the currently playing track.

The metadata for the audio tracks is extracted when the drive is scanned, and it is possible to display various metadata field, including BPM. If a track doesn’t have BPM information embedded, the SoundTouch library will attempt to analyse it.

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Figure 29 - Shows the “Library” section of the third UI design.

Figure 30 - Shows the “Settings” section of the third UI design.

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49 6.4.2 Talk Aloud Test Analysis Researcher comments Overall, the reaction from the participants was split. Participant A and D gave more positive comments and were less confused by how to use the system. This may be because they had used the system before (although the UI had changed quite a bit) or that they had been introduced to Vinyl already. Participant D even said (referring to using the previous UI design) “Definitely a lot easier to use than last time!” and could complete a basic mix, as opposed to the previous test when they could not.

Participant F and G gave mostly confused comments, and it took them a lot longer to work out how to use the interface. Neither could complete a basic mix.

One theme that arose was the lack of clarity over what UI elements they could interact with; Participant F’s first comments were: “First thing that I’m thinking is I'm not sure what’s a button on screen and what isn’t!”.

This was a feeling that was shared with the other participants. Participant G also asked for a feature that reduced the effect that the wow and flutter of the turntable had on the BPM, unaware that there was already a feature implemented that did that.

6.4.3 Self-Reporting Questionnaire Analysis

User Test 2 - Self-reflective questionnaire mean average score 2 1.5 1 0.5 0 Q1

Q2

Q3

Q4

Q5

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Test 2 Score

Figure 31 - Shows the user test 2 questionnaire scores. The results showed a mixture of positive and negativ scores when compared to test

Sam Spreadborough

50 Test 1 Mean Standard Average Deviation “The playback of the music file was fluid with no discernible audio errors” “The file was quick to load” “The application was fast to navigate” “I was able to find the music file I wanted to play quickly” “I was able to find all the functions and features that I wanted to use easily” “All the information I wanted was easily accessible” “The application gave me enough visual feedback” “The application had all of the functionality that I need” “I would feel confident using this as my primary DJing setup” “I was able to carry out the tasks in a way I’d want to do them” “The application was easy to learn” “I feel confident that I could use the product quickly and without errors” “I feel confident I could remember how to use this again”

Test 2 Mean Standard Average Deviation

Difference

0.80

1.10

1.00

1.41

0.20

1.80

0.45

1.50

0.58

-0.30

1.20

0.84

0.50

1.00

-0.70

1.40

0.90

1.75

0.50

0.35

0.40

0.90

0.00

1.83

-0.40

0.20

1.30

0.25

0.96

0.05

0.80

0.45

0.25

1.50

-0.55

0.00

0.71

0.00

1.15

0.00

-0.20

1.10

-0.75

0.50

-0.55

-0.40

0.55

0.25

1.50

0.65

1.20

0.45

1.50

0.58

0.30

0.20

0.84

0.00

0.82

-0.20

1.60

0.55

1.50

0.58

-0.10

The task completion metrics showed that 2/4 participants could complete a basic mix Of the 4 participants in this user test, half had used the project previously. In their questionnaire scores, they responded a lot more positively than the other two which makes interpreting the data difficult.

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51 The questionnaire raised the same issues that the user test found, in that participants.

However, interestingly, the participants responded that they felt the interface was easy to learn, however the comments during the user test was that the interface had a lack of affordance. So, based on that and their response to whether they could carry out the tasks in the way they wanted to that they thought the workflow worked for them, but needed to be educated on how to interact with that workflow.

However, in answer as to whether they could navigate the application quickly, they responded that they somewhat agreed (a reduction in score from the previous iteration).

Errors that prevent task completion

1. Overview waveform did not appear 2. Scrubbing only occurs when the waveform is dragged, no tapped 3. Cue points not clearing after new song is loaded 4. The wrong playlist content was showing based on the user playlist selection 5. Minor electric shock off the scroll knob 6. Screen turned off 7. Scrolling is not fluid

Suggestions for improvements

1. Multi-coloured waveform 2. Improve UI to give better feature understanding 3. Enclosure 4. Key information; show compatible keys

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6.5 User Test 3 – Improved modal tile design with greater affordance 6.5.1 Overview of Design changes Based on the feedback from user test 2, the following design changes were made: Tile representation Users reported being unsure what was a button and wasn’t a button. Named labels of what the button represented was added, along with new icons. A “windowed button” icon was added to the upper right of each tile to give more affordance that the “Tile” is a button that can be tapped to give greater affordance (Norman. 1988).

Figure 32 - Shows the overview screen for the third UI design.

Library The size of the file table rows was increased as was the text size. Users reported wanting to be able to view musical key information, and one user also requesting that the library show what songs are in a compatible key. A sorting algorithm was devised based on the circle of fifths, and compatible keys are displayed with a green background in the key cell.

Album artwork was added both to the library, as well as the Overview screen.

A new scanning function was written to combat the need to continually scan the library when the user selects a new playlist; the library is scanned in full when the drive is selected, and using a top down approach, the entire library is stored in an array.

A scroll bar for the file table was also reintroduced to give better clarity as to where about in the list the user was.

The width of the playlist table was reduced to accommodate the new width of the file table.

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Figure 33 - Shows the library for the third UI design.

Search The search feature was implemented in the new design, and an updated onscreen keyboard was designed to be more compact.

Figure 34 - Shows the updated on-screen keyboard for the third UI design.

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Pitch Drift Correction One user requested a feature where the wow and flutter of the turntable could be remedied. A new function was implemented that takes a 4 second snapshot of the pitch variations, returns the median value, and then sets the new pitch to that value. If the user manipulates the vinyl past a threshold, the feature deactivates and waits until the user is no longer manipulating the platter to restart the analysis process.

00:00:00 Button During the user testing, it became clear that users were using multiple different methods to return to the beginning of the track. Despite there being a cue point function that could be set at the beginning of the track, users frequently didn’t use this and opted to either use the static audio overview waveform to scrub to the beginning, spin back the vinyl until they got to the beginning, or reloaded the track again. A “00:00:00” button was added to make it simple to return to the beginning.

Beat Counter This was a feature that was requested at the group study stage, and had taken some time to implement correctly.

When the user connects and Ethernet cable between the two PiDVS players, OSC messages are sent carrying beat grid information that displays the beat counter for the connected player and that player.

Figure 35 - Shows the updated “Performance” screen for the third UI design with new Beat Counter feature.

Detailed Track Information Some users reported wanting to see the bitrate and file type of the songs in the file table. It wouldn’t be possible to display all this information in the limited space in the file table, so Sam Spreadborough

55 when the user taps on the album artwork on the Overview screen, a new screen appears showing an enlarged artwork image as well as more file information.

Figure 36 - Shows the new detailed track information screen for the third UI design.

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Figure 37 - Shows the back of the completed PiDVS project. The 3D printed legs were added to bring the height of the screen to above the height of the tonearm to prevent accidentally knocking. 2

2 Note: 3D printed legs Many user’s during testing would knock the tonearm accidentally due to the placement of the screen. 3D printed legs were designed and printed, however they were not ready for the final user test.

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57 6.5.2 Talk Aloud Test Analysis Of the 4 participants in this study, 3 had used the project previously.

Generally there were far fewer errors in participant understanding of the products, and the affordance changes to the icons had been successful. The same participant from test 2 who was most vocal about this gave a somewhat positive response.

Participants were pleased with the addition of the key compatibility indications and the artwork. All but the last participant was able to complete a basic mix (participant H had not used the project before and had not used vinyl before).

6.5.3 Self-Reporting Questionnaire Analysis

User Test 3 - Self-reflective questionnaire mean average score 2.00 1.50 1.00 0.50 0.00 Q1

Q2

Q3

Q4

Q5

Q6

Q7

Q8

Q9

Q10

Q11

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-0.50 -1.00 Test 2 Mea n Avera ge

Test 3 Mea n Avera ge

Figure 38 - Table shows user test 3 questionnaire results. All results are increases or no change when compared to user test 2.

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58 Test 2 Mean Average “The playback of the music file was fluid with no discernible audio errors” “The file was quick to load” “The application was fast to navigate” “I was able to find the music file I wanted to play quickly” “I was able to find all the functions and features that I wanted to use easily” “All the information I wanted was easily accessible” “The application gave me enough visual feedback” “The application had all of the functionality that I need” “I would feel confident using this as my primary DJing setup” “I was able to carry out the tasks in a way I’d want to do them” “The application was easy to learn” “I feel confident that I could use the product quickly and without errors” “I feel confident I could remember how to use this again”

Test 3 Difference Standard Mean Standard Deviation Average Deviation

1.00 1.50

1.41 0.58

1.50 1.75

0.58 0.50

0.50 0.25

0.50

1.00

1.50

1.00

1.00

1.75

0.50

1.75

0.50

0.00

0.00

1.83

0.25

1.50

0.25

0.25

0.96

1.25

0.96

1.00

0.25

1.50

1.00

0.82

0.75

0.00

1.15

0.50

0.58

0.50

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0.00

1.15

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0.25

1.50

1.00

1.41

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1.50

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0.00

0.00

0.82

0.00

1.15

0.00

1.50

0.58

1.75

0.50

0.25

In all areas of the self-reporting questionnaire, the participants reported improvements or no change over the previous UI iteration.

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7 Conclusion 7.1 Summary There are now more ways to DJ than ever before, and the research results have shown that there isn’t a single set of design requirements that fit all DJing styles. The research has shown, however, for modern computer based DJs there are an essential list of requirements that reflect how traditional turntable based DJs operate.

The research results have indicated that the essential set of requirements for a computer based DJ are visual waveform display, track selection table, search, file metadata (including key and BPM) and cue points. These are all analogous with the basic use case of the turntablist (e.g. turntablists use stickers for cues; Controllerists use cue points. Turntablists will view the waveform cut in the to the vinyl; Controllerists use a visual scrolling waveform).

The UX requirements for an embedded DVS system are virtually identical to a user of DVS software’s in terms of functionality and UI design, however it has its own unique UX requirements in its form factor. The positioning of the screen, for example, is unique to other multimedia players due to the height and location of the tone arm. Many users knocked the needle when trying to access the touch screen. In addition, many user reported disliking touch screen interfaces as it hindered their ability to DJ with virtuosity. An embedded turntable would need to include a range of interactions to accommodate for all user preferences.

7.2 Evaluation of finished product DJWORX featured this project on their website providing details to the public (Settle, M. 2017). The comments section of the article provided useful feedback with many commentators praising the work (especially the UI). The article sparked a debate amongst several commentators regarding the final form factor of the project with one saying that they’d prefer a standalone unit compared to an embedded system. Several readers commented that they’d like a single unit that could power two decks rather than a single unit per deck.

Regarding the functionality, there were differing views. Dan Morse gave this comment: “Thing is, real vinyl effectively gives you an indication of what's going on in the music, without which, it would be a massive hassle. I agree that scrolling waveforms are a luxury rather than necessity for this, and a low res screen with the track waveform with progress indicator, the name of the file, and some playlists access, would be all you need.”

Whereas Mark Settle gave this counter argument: “It makes sense for [the researcher] to reach further than necessary.

For every "I don't need all that stuff" comment, there will be an equal number of "no loops or cues? EPIC FAIL" comments.”

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Overall there was a lot of enthusiasm for the project with many commentators making enquiries to when it would be commercially available. Settle (2017) remarked in the article that: “If ever there was a commercially viable product, it’s this”.

The project was also featured on the DJ TechTools website. The views of commenters from their Facebook post were varied. Gavin Varitech wrote: “Talk about taking a step backwards in a quest towards something no one(sic) wants or needs” during a discussion around the authenticity of vinyl DJing. Another commentator wrote: "If your(sic) not trying to use a laptop just REAL Vinyl”.

From the user testing point of view, there was a significant increase in self-reporting questionnaire results from revision 1 to revision 3. Participant A in user test 3 stated in their questionnaire: "Very fluid experience, would consider using it as my main device. Very fun!"

7.3 Future work 7.3.1 Changes to hardware

The most requested feature for the system was a multi-coloured waveform. This was not possible to achieve within the timespan, however is a feature that would be possible to implement using a 3-band filter and mapping the results to RGB colour values.

A master tempo, or pitch lock, feature was also suggested. Although it was experimented with, the overall audio lag made the feature unusable. This could either be due to the algorithm used or the limited processing power of the Raspberry Pi 3 Model B. Through further experimentation, it should be possible to find a solution that balances sound quality with latency.

Although the PiDVS system can perform well using a phono level signal, the best performance comes when a line level audio input is used. As further work, a phono preamp would be built in to a complete enclosure.

The scope of this project goes further than designing one product. The technology industry has seen a growth in embedded software due in part to the new Internet of Things (IoT) and wearables market. The growing popularity of the Raspberry Pi and with computer coding now being more accessible to people than ever before. The DJ technology industry has been reluctant to make this move, with notable exceptions with Pioneer and their range of CDJ Sam Spreadborough

61 and XDJ multimedia players, however the future of the technology industry will be in embedded software.

Figure 39 - Potential design for an embedded PiDVS system. Scroll knob and cue buttons are built in to the turntable.

Figure 40 - Back view of potential design for an embedded PiDVS system.

[Words: 13,056]

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87.

Tullis, T. and Albert, B. (2010) Measuring the User Experience. 1st ed. Burlington, MA: Morgan Kaufmann Publishers.

Van Veen, T.C. (2011) OFF THE RECORD: TURNTABLISM AND CONTROLLERISM IN THE 21ST CENTURY (PART1) Dancecult: Journal of Electronic Dance Music Culture. 3 (1), pp.21 September.

Watson, K., (2015) IMS Business Report 2015: North America Edition A Study of the Regional Electronic Music Industry. Ibiza, Spain: IMS. Waveshare 7 Inch HDMI LCD (B) - Waveshare Wiki. Available from: http://www.waveshare.com/wiki/7inch_HDMI_LCD_(B) [Accessed 3 April 2017].

Wax and Stamp (2017) Wax and Stamp. Available from: http://www.waxandstamp.com/ [Accessed 7 April 2017].

Web, D. (2011) List of Juce Dependencies Under Linux. JUCE Community, [online].

Available from: https://forum.juce.com/t/list-of-juce-dependencies-underlinux/15121 [Accessed 10 September 2016].

White, D. (2016) What is Portablism? 2016 is the Year of the Portable Turntable DJ. Available from: http://djtechtools.com/2016/08/01/portablism-2016-year-portableturntable-dj/ [Accessed 3 April 2017].

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9 Appendix Table of Content

1

Glossary of Terms..............................................................71

2

Participant Paperwork........................................................74

2.1 2.2 2.3 2.4 2.5

3

Group Study – Consent Form..................................................................................................74 Group study – Self-reporting questionnaire............................................................................77 Group study – Group Activity.................................................................................................78 User Test – Consent Form.......................................................................................................80 User Test – Self-reporting questionnaire................................................................................83

Raw Research Data............................................................86

3.1 Existing DJ product list............................................................................................................86 3.1.1 Software Comparisons.......................................................................................................88 3.2 User Test 1..............................................................................................................................90 3.2.1 User Test 1 – Participant 1 - Think Aloud Data...................................................................90 3.2.2 User Test 1 – Participant 2 - Think Aloud Data...................................................................92 3.2.3 User Test 1 – Participant 3 - Think Aloud Data...................................................................94 3.2.4 User Test 1 – Participant 4 - Think Aloud Data...................................................................95 3.2.5 User Test 1 – Participant 5 - Think Aloud Data...................................................................96 3.3 User Test 2..............................................................................................................................97 3.3.1 User Test 2 – Participant 1 - Think Aloud Data...................................................................97 3.3.2 User Test 2 – Participant 2 - Think Aloud Data...................................................................99 3.3.3 User Test 2 – Participant 3 - Think Aloud Data.................................................................101 3.3.4 User Test 2 – Participant 4 - Think Aloud Data.................................................................103 3.4 User Test 3............................................................................................................................104 3.4.1 User Test 3 – Participant 1 - Think Aloud Data.................................................................104 3.4.2 User Test 3 – Participant 2 - Think Aloud Data.................................................................105 3.4.3 User Test 3 – Participant 3 - Think Aloud Data.................................................................107 3.4.4 User Test 3 – Participant 4 - Think Aloud Data.................................................................108

4

Collated Research Data....................................................110

4.1 Self-reporting Questionnaires...............................................................................................110 4.1.1 User Test 1........................................................................................................................110 4.1.2 User Test 2........................................................................................................................113 4.1.3 User Test 3........................................................................................................................116

5

USB Contents List............................................................118

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1 Glossary of Terms Terms Beat Matching Beat Mixing Beats Per Minute Booth BPM

Break

Camelot Wheel CDJ

Controller Crossfader

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Definition The technique of pitch shifting or time stretching a track to match its tempo to what is playing through the speakers.

The technique of playing two songs at the same time so that the beats of one song occur at the same time as the other, blending the tracks.

The number of steady, rhythmic pulse per minute of time in a music selection which establish the tempo of the song The DJ workstation where equipment is set up and operated.

An abbreviation of Beat Per Minute 1) A bit of a song which sounds great and could maybe be used as a sample to make a new “hook” or “riff” with.

2) A change in a song where one or more instruments stops playing.

3) A change in a song where one instrument does something different eg a drum fill.

A break is distinguishable from a solo as the change will normally not last too long.

A colour-coded system invented by Mark Davis that helps you determine which musical keys are compatible. Each key is assigned a code number from one to twelve, like the hours around a clock. The wheel is visually designed to help you learn harmonic mixing.

A line of CD players from Pioneer Electronics that allow analogue control of music from CD’s, using an emulated vinyl control surface.

“USB Controllers” are hardware units which utilise “DJ Software” on PC or MAC computers. USB Controllers should have all the controls a DJ may want. Some of the best controllers also provide audio out for a computer, Some controllers act as DJ “mixers” and allow other CD or Vinyl “decks” to be included. There are also USB Controllers which act as midi controllers over other elements of DJ Software. Big players in the Controller market are: Pioneer, Vestax, Numark, and most other hardware manufacturers. Big players in DJ software include: Traktor, Serato, ITCH and others.

A transitional slide control on a mixer for fading in one input channel while fading out another.

71 1) to prepare a song to be played. Normally a Dj chooses a point from which to begin a tune that is the beginning of the first beat of the first bar, or occasionally the beginning of the audio if these are not the same. More experienced DJs get creative by cueing from anywhere 2) to cue up can also be used to describe the action of setting an audio path so you can hear something in your headphones 3) on a CDJ, DVS or Controller deck the cue button is used to stutter the beginning of a song or to set a “cue point” which is where the song will begin to play from

Cue Deck

DVS Fade Flutter Jog Wheel Loop MC Mix Pitch Lock Pitch bend Platter

Record Residency Scratch Sam Spreadborough

4)On some DJ mixers the cue button for a channel will select that channel to be played through the headphones.

Player of CDs or vinyl records. Sometimes it’s called a “turntable”.

Also known as DVS a digital vinyl system contains DJ software running on a computer which plays back music contained on the computer but which is controlled by using either “CD” or “Vinyl” “decks”.

A gradual increase or reduction in the level of the audio signal.

2) To slowly change the level of an audio signal from one level setting to another.

1) High-frequency pitch variations in program material due to speed fluctuations in a recorder or playback unit. Often expressed as "wow and flutter".

A type of knob, ring, wheel, or dial which allows the user to shuttle or jog through audio or video media most commonly referenced in relation to a Pioneer CDJ CD player.

A seamless repeat of an audio sample or musical segment.

An abbreviation for ‘Master of Ceremonies’ or ‘Mic Controller’.

Any way you choose to swap between two songs.

The ability of a device to change the tempo of a song, without changing the pitch. This lets you drastically speed up songs with vocals without a "chipmunk" effect.

An electronic device or control that enables a player to bend the pitch being sounded, usually with a pitch wheel, strip, or lever.

The plate on top of a turntable (or replicated on a Pioneer CDJ) that is rotated by the motor or belt to play music.

A thin disc of a vinyl plastic material upon which sound has been recorded. Each side has a spiral groove, which undulates in accordance with the frequency and amplitude of the sound.

Often used in slang referring to a track, album or music release.

A collection of repetitive DJ performances at one venue on an exclusive basis usually pertained to the geographical territory.

Move the disc back and forth with your hand to alter the music,

72

Set

Slip cue Slip mat Spin back

Throwing Waveform Wow

Sam Spreadborough

normally done with another song playing as a background.

A DJ mix or DJ mixset is a sequence of musical tracks typically mixed together to appear as one continuous track. When a DJ mix or DJ mixset is recorded onto some medium, it is often referred to as a mix tape or compilation.

A record cue technique that involves rocking the record back and forth by hand to locate the desired start position. Once located, the DJ holds the record in position by hand and then releases it on cue to achieve near instant start up.

A circular piece of felt-type material used by DJs in place of the rubber mat to provide slippage for slip cueing and scratching techniques.

The action of spinning a record on a turntable in reverse.

Giving a record a little push when it starts up so you don't have any lag time while it gets up to speed. CD players do this by featuring instant start. (normal CD players may take a few tenths of a second before a song starts) Throwing a record nulls the lag time while it accelerates from zero to 33ish RPM. It sounds silly at first but it is actually very critical for Beatmixing.

The shape of an audio wave, with all its fluctuations, over a given period.

Low pitch changes in a recorded program due to slow and gradual changes in the speed of the record or playback device.

73

2 Participant Paperwork 2.1 Group Study – Consent Form

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2.2 Group study – Self-reporting questionnaire

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2.3 Group study – Group Activity

Group name

Please use the rectangles below to design your ideal user interface. The entire interface doesn't have to be on one rectangle; it could be split in to many.

If you’d like more paper, please ask!

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2.4 User Test – Consent Form

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2.5 User Test – Self-reporting questionnaire

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3 Raw Research Data 3.1 Existing DJ product list Software

Virtual DJ Serato DJ Traktor DJ / Traktor Scratch Rekordbox

Laptop Controllers

Numark NS7III Novation Twitch Traktor Kontrol S8 Pioneer DDJ-RX

Standalone Controllers

Pioneer XDJ-RX Denon MCX8000 Numark Mixdeck

Tablet Controllers

Numark iDJ Pro Traktor Kontrol Z1 Reloop Beatpad

Supplementary Controllers Novation Dicers Pioneer DDJ-SP1 Vinyl Emulation Software

Serato DJ Traktor Scratch Rekordbox

Tablet Software

DJAY Pro Cross DJ Traktor DJ Tonetable

Multimedia Players

Pioneer CDJ 2000NXS2 Pioneer XDJ-1000 Gemini MDJ-1000 Denon DJ SC5000

Non-commercial systems

PiDeck Rwax Andrei Anantsko standalone Technics DVS ThudRumble Mixer

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87 3.1.1 Software Comparisons

Virtual DJ

Serato DJ

Traktor Pro 2

Audio Overview Waveform

X

X

X

X

Scrolling Waveform File Library Hot Cues Loops

X X 8 X

X X 8 X

X X 32 X

X X 8 X

BPM Display Pitch Lock Effects

X X X

X X X

X X X

X X X

Music Streaming Service Compatible

X

X

X

X

X

Require Specialised Hardware MIDI Controller Compatible

Supported Audio Formats DVS Latency < 10ms Requires Proprietory Timecode Vinyl Pitch Drift Correction Beat Matching assistance (Other than stacked Waveforms)

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Rekordbox DVS

X

Limited

X

Limtied

MP3, WAV, CDA, WMA, ASF, OGG, M4A, AAC

MP3, OGG, AAC, ALAC/FLAC , AIF, WAV, WL.MP3

MP3, WAV, AIFF, CDA, FLAC, OGG, WMA, AAC

ALAC, FLAC, WAV, AIFF, MP3, AAC

X

X

X

X

X X

X

X

X

X

X

88

Audio Overview Waveform Scrolling Waveform File Library Hot Cues Loops BPM Display Pitch Lock Effects Music Streaming Service Compatible

DJAY Pro

Cross DJ

Traktor DJ

X

X

X

X X X X

X X X X

X X X X

X X X

X X X

X X X

X

X

X

X

Require Specialised Hardware External Controller Compatible Beat Matching assistance (Other than stacked Waveforms ) Supports DVS

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X

89

3.2 User Test 1 3.2.1 User Test 1 – Participant 1 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated frustration

Timestamp

Metric

00:34 Behavioural 00:42 Error 01:13 Behavioural 01:57 Behavioural

03:24 Issue 04:00 Behavioural 04:34 Error Sam Spreadborough

Participant A Rating Comment "Seems to be running quite fluidly. Its quite B good" User tries to scroll file table using finger in C the centre of the screen.

"So that’s good that you can see the keys on B there."

"Just testing some scratching…. Seem's to B work quite well" Audible squeal from audio glitch. The software outputs glitch when the play head is pulled back behind the beginning of the Low audio track.

"Lets see how slow downs go… Ok, works B well" User tries to use the turntable stylus lever to D raise tonearm, but is broken

90

04:42 Issue 04:51 Behavioural

Low B

04:51 Behavioural

F

04:56 Behavioural 05:18 Issue

B High

06:34 Behavioural 07:14 Behavioural 07:31 Behavioural

D B F

07:58 Behavioural

E

08:17 Issue 08:52 Behavioural

High B

09:25 Error

C

09:40 Behavioural

F

09:50 Behavioural

B

Sam Spreadborough

Software detecting grounding issues as timecode pitch, and an audible glitch is heard "Reacts quite well" "Does it jump?" (referring to whether the needle position on the vinyl affects the playback position) "Its pretty much like a Serato setup where it doesn’t matter where it is on the vinyl. That’s pretty good, actually. I prefer that" Software crash "As a controller DJ, I'd say the only thing at the moment that is quite tricky is finding your beat in there. Being a controller DJ and seeing the screens, you kinda get the BPM off both. Over here it’s a lot more listening to music, which is good, but its a hell of a lot harder. " "It runs quite well actually."

"What do these do? … Oh they’re cue points" Add cue point label. User didn’t realise they were cue points When app settings are launched, the sound stops "Got a nice keyboard" User tries to hide keyboard, but isn’t immediately aware of the "Hide" button on onscreen keyboard "Are these just folders on the thing?"

(Referring to how the music is stored on the USB drive) "That’s pretty cool!" (When explaining how the analysis of the tracks takes place)

91

3.2.2 User Test 1 – Participant 2 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated frustration

00:26 Behavioural 00:41 Behavioural

Participant B Rating Comment Scrolling touching the main screen rather E than scroll bar E BPM information

00:52 Issues

Low

00:52 Error 01:42 Issues

C Low

Timestamp

Metric

User not able to find out how to load track User tries to load song by double tapping the file table row Left deck screen went to standby mode

06:06 Behavioural

H

06:23 Behavioural 06:34 Behavioural

F B

User shows some frustration at not being able to mix the song. Possibly due to unfamiliarity with Vinyl DJing “I'm wondering why the BPMs [pitch percentage] is currently changing” “The concept is good, I like how it works”

06:50 Behavioural

E

BPM steady; key information colour coded

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92 07:26 07:34 07:38 07:50

Behavioural Behavioural Behavioural Behavioural

B E E B

07:58 Behavioural

F

08:00 Behavioural

B

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“It’s cool though. I like it” Bigger waveform Static waveform overview “I like how the players are laid out” Is that a 30 second countdown? Why its flashing red?

“I like that. That’s good” (referring to countdown flash)

93 3.2.3 User Test 1 – Participant 3 - Think Aloud Data Errors Metric - Key A Slip B Mistake C User Interface Problem D Equipment (other than project) failure Issues Metric - Key "Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated frustration

Timestamp

Metric

00:47 Behavioural 01:11 Error 01:17 Error 02:13 Behavioural 02:13 Error 03:42 Behavioural 05:06 Behavioural 06:32 Behavioural 08:51 Behavioural

Sam Spreadborough

Participant C Rating Comment User has put stylus on vinyl record but is H confused to why there is no song playing User tries to scroll file table using finger in C the centre of the screen.

C User not able to find how to load song User is trying to cue up the track, but D having difficulty with using the vinyl User tries to scrub through the track but C dragging the waveform User is trying to cue up the track, but D having difficulty with using the vinyl User is trying to cue up the track, but I having difficulty with using the vinyl “It’s quite responsive! I like you can literally see straight away what is going B on” E See the BPM

94 3.2.4 User Test 1 â&#x20AC;&#x201C; Participant 4 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated frustration Participant D Timestamp Metric 00:08 Error VIDEO ENDS DUE TO LACK 02:28 OF STORAGE

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Rating Comment User tries to scroll file table using finger in the centre of C the screen.

95 3.2.5 User Test 1 – Participant 5 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated frustration

Timestamp Metric 00:04 Behavioural 00:25 Behavioural 01:04 Behavioural 01:31 Error 03:22 Behavioural 04:16 Behavioural 06:10 Behavioural 07:06 07:29 10:21 10:56

Behavioural Behavioural Behavioural Behavioural

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Participant E Rating Comment F “Is that track loaded already?”

E Static overview waveform “I can't see any BPMs on here, so I'll have G to beat match manually” C Dirty stylus/vinyl “Waveform is really limited at the D moment” F “How do I go back to the beginning?”

F “Does it have hot cues at all?”

“Good integration with the mixer is always E good” B “Nice and clear” B “The pitch control works really well” E Loops

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3.3 User Test 2 3.3.1 User Test 2 – Participant 1 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated frustration

Timestamp

Metric

Participant A Rating Comment

00:22 Behavioural 00:59 Behavioural 01:35 Issue

B B Medium

02:36 Behavioural

B

03:37 Issue 04:29 Behavioural

Low B

04:41 Error

D

05:19 Behavioural

B

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(When scrolling library with finger) “Much better than the other version in terms of scrolling ability” “It shows the BPM, so that’s quite cool” Overview waveform did not appear (Referring to the speed at which the pitch fader changes the BPM display) “Its quite responsive” Scrubbing only occurs when the waveform is dragged, no tapped “I don’t hear any audible noise” Left hand deck is broken. Grounding issue/Dirty contacts (Refering to scratching latency) “Its quite responsive”

97

05:57 Behavioural 06:17 Behavioural

B E

07:01 Error

B

07:11 Behavioural

B

07:20 Behavioural

E

08:53 Issue 10:38 Behavioural 10:40 Behavioural

Low B E

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“The interface looks a lot better than the other one … A lot nicer laid out” Multi-coloured waveform User pressed the Play screen button by accident not realising what it does (When user is shown the play screen mode) “That’s pretty cool!”

"Performance" - User confused what the top button did Cue points not clearing after new song is loaded “Cue point works quite well” Sturdier enclosure

98 3.3.2 User Test 2 – Participant 2 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated frustration

Timestamp Metric 01:25 Behavioural 02:55 Behavioural 03:22 Behavioural 04:52 Issue 05:23 Behavioural 06:00 Behavioural 06:15 Error 06:48 Issue 07:40 Behavioural 08:12 Behavioural 08:45 Error Sam Spreadborough

Participant D Rating Comment B “BPM is a good addition” B “A lot easier to understand” (Referring to Track Playing warning) “I like B that” The wrong playlist content was showing Low based on the user playlist selection (Referring to waveform) “Easy to find first B beat” “Definitely a lot easier to use than last A time” User tried to drag finger along overview C waveform, not realising it’s a button Low Minor electric shock off the scroll knob (When shown the beat counter) “That is B useful” B “Definitely helpful seeing the beats there” User unaware that the waveform buttons C in the play screen can be tapped to zoom

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08:56 Behavioural

B

10:15 Error 11:25 Behavioural

C E

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“It’s also seeing what songs you've played.

That’s another positive feature” User unaware that the static waveform can be scrubbed with finger Screen is higher

100 3.3.3 User Test 2 – Participant 3 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated frustration

Timestamp

Metric

00:17 Behavioural 01:45 Issues 02:15 Issues 03:43 Behavioural 04:56 Behavioural 05:21 Behavioural 06:43 Error 07:16 Behavioural

07:51 Behavioural

Sam Spreadborough

Participant F Rating Comment "First thing that I’m thinking is I'm not sure H what’s a button on screen and what isn’t!"

Low Screen turned off Low Scrolling is not fluid User confused how to return the track back H to the beginning Wow and flutter from turntable is causing I the user to feel frustrated E Wow and flutter correction User tries to return to the overview screen C by tapping the zoom button User is confused about relative and H absolute modes

H

Having shown the user how to place a cue point, the user is still unsure of how to place one

101

07:51 Error 09:42 Error

C D

10:49 Behavioural

I

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User unaware that the static waveform can be dragged Turntable grounding/dirt issue A lot harder than it looks to get a tune in time

102 3.3.4 User Test 2 – Participant 4 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated frustration

Timestamp

Metric

01:34 Error 02:19 Behaviour 05:25 Behaviour 06:15 Behaviour

06:50 07:24 08:08 09:10 10:10

Error Behaviour Behaviour Error Behaviour

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Participant G Rating Comment User trying to load track by double tapping C the song D “BPM is fluctuating the whole time” F “Are there cue points?”

User confused to what the pitch drift F correction does

C E E D E

User trying clear the cues, however not realised the they must tap the cue you want to clear.

Key information; show compatible keys Requesting pitch ranges further than +/- 8% Dirty turntable Noise gate to prevent background vibration

103

3.4 User Test 3 3.4.1 User Test 3 â&#x20AC;&#x201C; Participant 1 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated fustration

Timestamp

Metric

Participant D Rating Comment

00:17 Behavioural 00:44 Behavioural

B D

04:10 Behavioural 05:05 Behavioural

H H

Refering to inclusion of icons to indicate buttons "Jumpy" scrolling of the file table "I can't remember from last time. Was there always a playlist of genres there last time?"

"Did it always have the stop deck before?"

06:28 Behavioural

G

"Oh! They have the beatcounter like the CDJs have"

H G H

"I didnâ&#x20AC;&#x2122;t realise that was a button." When refering to the Performance button Explaining the 00:00:00 button.

Finding it difficult to mix using vinyl

06:33 Behavioural 08:10 Behavioural 10:25 Behavioural

Sam Spreadborough

104 3.4.2 User Test 3 – Participant 2 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated fustration

Timestamp Metric 00:25 Behavioural

Participant D Rating Comment B "Looks pretty good"

00:29 Behavioural 00:36 Behavioural

B B

01:26 Behavioural

B

"Buttons are little bit wider [taller]. That’s nice!"

"Colours of the keys are pretty cool" "Looks quite nice. A little different than before. You got the visuals in there; which is good. With the artwork. The buttons are a lot better laid out. You can actually see to get in to the performance section which is good"

02:04 Behavioural 02:26 Behavioural

B B

Refering to the beatcounter - "Its cool to see them connected now" Refering to the loops " That’s pretty cool!"

02:38 Behavioural

A

03:29 Behavioural

B

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Refering to the 00:00:00 button "I really like that" "Very responsive. Still has a fluid experience"

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B D

Refering to static waveform - enjoyed that functionality Connected deck stacked waveforms

06:06 Behavioural 06:28 Behavioural 06:59 Behavioural

A E B

Refering to Detailed Artwork tab "That’s cool!"

Suggestion for Bitrate information "Feels more fluid"

07:20 Behavioural

B

Enjoys the modal BPM/Pitch display on overview component

B

"If someone can play Vinyl, they can pick up this system up straight away"

B

Refering to compatible key indication "That’s pretty cool!"

03:30 Behavioural 05:06 Behavioural

07:42 Behavioural 08:16 Behavioural 08:25 Behavioural

H

08:58 Behavioural

B

Participant trying to use the sort feature on the filetable. Not yet implemented Refering to artwork in filetable "That’s quite handy!"

Medium

Bug with search feature. The selected deck needs to be changed to be the top of the filetable otherwise the searched results disappear

09:32 Issue

Sam Spreadborough

106 3.4.3 User Test 3 â&#x20AC;&#x201C; Participant 3 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated fustration

Timestamp 00:19 00:49 01:14

Metric Behavioural Behavioural Error

Participant F Rating Comment B "Artwork is nice little touch" B "I like that its got the search the song now" D Turntable not picking up timecode signal

03:50 Behavioural

B

Refering to the button names on overview "Clear headings"

04:53 Behavioural

H

Lack of understanding about what the 00:00:00 button did

F B B

Refering to the compatible key system "Does it light up if itâ&#x20AC;&#x2122;s a compatible key?"

"Thats good!"

Enjoyed using the quantised looping.

06:05 Behavioural 06:10 Behavioural 08:28 Behavioural

Sam Spreadborough

107 3.4.4 User Test 3 â&#x20AC;&#x201C; Participant 4 - Think Aloud Data Errors Metric - Key A B C D

Slip Mistake User Interface Problem Equipment (other than project) failure Issues Metric - Key

"Any issue that annoys or frustrates participants but does not play a role in Low task failure" Medium "Any issue that contributes to but does not directly prevent task failure" High "Any issue that directly leads to task failure" Behavioural Metric - Key A Strongly positive comments B Other positive comments C Strongly negative comments D Other negative comments E Suggestions for improvement F Questions G Variation from expectation H Stated confusion or lack of understanding I Stated fustration Participant had never used vinyl before so many of the stated issues were to do with a lack of understanding of how vinyl works Participant H Timestam p Metric Rating Comment Behavioura 00:54 l F "Has the key detection already loaded?"

Behavioura 01:30 l

B

"Very similar to other things I've used like Serato and that"

Behavioura 02:07 l 03:35 Error

H D

Participant neeed some explanation of how DVS works Dirty turntable

High

When the loop out point is set to be less than one beat, the in and out loop points are the same and there is a high pitched noise

F

"Pitch correctionâ&#x20AC;Ś Is that pitch lock?" Participant needed some explanation

04:38 Issue Behavioura 04:48 l

Sam Spreadborough

108 Behavioura 05:18 l Behavioura 05:38 l

B

Refering to the beat counter "I like that it counts the bar, similar to like the CDJ"

E

Coloured waveform

H

Participant didnâ&#x20AC;&#x2122;t know what the 00:00:00 button did

Behavioura 06:41 l

B

"You can needle search during the track. I kinda like that"

Behavioura 07:47 l

B

"I like that you can actually scroll using the app rather than using the scroll bar on the side"

Behavioura 07:49 l

B

"Its way quicker than twisting [the scroll knob] on the CDJ"

Mediu m

Despite the turntable being stationary, the dialog box indicating the file cannot be loaded unless the turntable has stopped still appears

I

"I can't mix on vinyl apparently"

H

Explained to participant that the whole of the performance tile is a button

F

"How to you load the tracks?"

Behavioura 06:09 l

08:18 Issue Behavioura 09:42 l Behavioura 10:20 l Behavioura 10:37 l

Sam Spreadborough

4 Collated Research Data 4.1 Self-reporting Questionnaires 4.1.1 User Test 1 User Test 1 Question “The playback of the music file was fluid with no discernible audio errors” “The file was quick to load” “The application was fast to navigate” “I was able to find the music file I wanted to play quickly” “I was able to find all the functions and features that I wanted to use easily” “All the information I wanted was easily accessible” “The application gave me enough visual feedback” “The application had all of the functionality that I need” “I would feel confident using this as my primary DJing setup” “I was able to carry out the tasks in a way I’d want to do them” “The application was easy to learn” “I feel confident that I could use the product quickly and without errors” “I feel confident I could remember how to use this again”

Sam Spreadborough

Participant A Score

Participant Participant B Score C Score

Participant D Score

Participant Total E Score Score

Standard Deviatio

1 2 1

1 2 0

1 2 2

2 1 1

-1 2 2

0.8 1.8 1.2

1.10 0.45 0.84

2

0

2

2

1

1.4

0.89

1 2 1 1

-1 -1 1 0

0 -1 1 -1

1 1 1 0

1 0 0 0

0.4 0.2 0.8 0

0.89 1.30 0.45 0.71

0

0

-2

0

1

-0.2

1.10

-1 1

0 1

-1 1

0 1

0 2

-0.4 1.2

0.55 0.45

-1

1

1

0

0

0.2

0.84

2 12

2 6

2 7

1 11

1 9

1.6 9

0.55 0.78

If you felt that there was anything missing from the software, please make a comment in the box below:

BPM Multicoloured waveform Virtual pitch fader

Loops Beat grid Full song waveform What improvements, if any, would you want to see to this product?

Touch scroll BPM lists Bug fixes to noise Pre-amp taming More intuitive interface Beat grid Coloured Waveform If you have any overall thoughts or comments to make about the project in general, please leave them in the box below

Participant A "This device is amazing, would definitely use it as it combines the analog and digital world!"

Participant B "Really good idea, interface change" Participant C "Overall a good idea, lots of potential" Participant D "Very intelligent software to all those who want to learn vinyl & facilitate vinyl mixing" Participant E BLANK

Sam Spreadborough

Sam Spreadborough

4.1.2 User Test 2 User Test 2 Previous participants Question “The playback of the music file was fluid with no discernible audio errors” “The file was quick to load” “The application was fast to navigate” “I was able to find the music file I wanted to play quickly” “I was able to find all the functions and features that I wanted to use easily” “All the information I wanted was easily accessible” “The application gave me enough visual feedback” “The application had all of the functionality that I need” “I would feel confident using this as my primary DJing setup” “I was able to carry out the tasks in a way I’d want to do them” “The application was easy to learn” “I feel confident that I could use the product quickly and without errors” “I feel confident I could remember how to use this again”

Participant Participant Participant Participant Total A Score D Score F Score G Score Score 2 1 1

1 2 1

-1 1 1

2 2 -1

1.00 1.50 0.50

1.41 0.58 1.00

2

2

1

2

1.75

0.50

1 0 -1 1

2 1 2 1

-2 -1 1 -1

-1 1 -1 -1

0.00 0.25 0.25 0.00

1.83 0.96 1.50 1.15

-1

0

-1

-1

-0.75

0.50

2 2

1 1

-1 2

-1 1

0.25 1.50

1.50 0.58

0

1

0

-1

0.00

0.82

2 12

1 16

1 0

2 3

1.50 7.75

0.58 0.99

If you felt that there was anything missing from the software, please make a comment in the box below:

Sam Spreadborough

Standard Deviation

Multi-coloured waveforms Key information FX shown on screen

Exact BPM. One that doesn’t fluctuate The ability to sort the display of music Ability to change loop length What improvements, if any, would you want to see to this product?

Slightly more visual experience but with more labelled sections Slight delay on the cue button Less juderry screen No cursor Make obvious what is buttons and what isnt Visually: Different colours in the wavelentgh for instrument Hardware: Ability to change angle of the screen If you have any overall thoughts or comments to make about the project in general, please leave them in the box below

Participant A "Great device with massive potential" Participant D "Really good idea, interface change" Participant F "Really cool idea! Just need refining. A lot of people will enjoy this" Participant G "I think the project could be very helpful for beginners wanting to learn vinyl, and could be a cheaper way for them to do so"

Sam Spreadborough

4.1.3 User Test 3 User Test 3 Previous Participants Question “The playback of the music file was fluid with no discernible audio errors” “The file was quick to load” “The application was fast to navigate” “I was able to find the music file I wanted to play quickly” “I was able to find all the functions and features that I wanted to use easily” “All the information I wanted was easily accessible” “The application gave me enough visual feedback” “The application had all of the functionality that I need” “I would feel confident using this as my primary DJing setup” “I was able to carry out the tasks in a way I’d want to do them” “The application was easy to learn” “I feel confident that I could use the product quickly and without errors” “I feel confident I could remember how to use this again”

Sam Spreadborough

Participant Participant Participant Participant Total Standard D Score A Score F Score H Score Score Deviation 1 1 0

2 2 2

1 2 2

2 2 2

1.50 1.75 1.50

0.58 0.50 1.00

1

2

2

2

1.75

0.50

-1 0 1 0

2 2 1 1

1 2 2 1

-1 1 0 0

0.25 1.25 1.00 0.50

1.50 0.96 0.82 0.58

-1

1

1

-1

0.00

1.15

-1 1

2 2

2 2

1 1

1.00 1.50

1.41 0.58

-1

1

1

-1

0.00

1.15

1 2

2 22

2 21

2 1.75 10 13.75

0.50 0.86

If you felt that there was anything missing from the software, please make a comment in the box below:

Multicoloured waveform in the performance section What improvements, if any, would you want to see to this product?

"More obvious what is a button and what isnt" "Multicoloured waveform" "Slightly more accurate BPM counter" If you have any overall thoughts or comments to make about the project in general, please leave them in the box below

Participant D Intentially Blank Participant A "Very fluid experience, would consider using it as my main device. Very fun!"

Participant F "Good product, much more readily easy to use than first one" Participant H "Pretty cool, would be interested if I used vinyl"

Sam Spreadborough

5 USB Contents List 5.1 Code Project 5.1.1  5.1.2 

Project Files /Code Project/ Project Files (UI Design 3) Stable 23Feb17 Executable /Code Project/PiDVS.app

5.2 Demo 5.2.1  5.2.2 

Demo Videos /Demo/Demo Videos/ PiDVS – Instructions /Demo/PiDVS – Instructions.pdf

5.3 Group Study Activity – User Designs 

/ Group Study Activity - User Designs/

5.4 Photos 

/Photos/

5.5 PiDVS User Manual 

/PiDVS User Manual.pdf

5.6 Research Videos 5.6.1  5.6.2  5.6.3  5.6.4 

Group Study /Research Videos/Group Study/ User Test 1 /Research Videos/User Test 1/ User Test 2 /Research Videos/User Test 2/ User Test 3 /Research Videos/User Test 3/

Sam Spreadborough